Structure Data of Free Polyatomic Molecules
817
C7H20N3P
ED, ab initio
calculations
ra
P=C
P–N(1,2)
P–N(3)
N(1,2)–C
N(3)–C
C–H b)
N,N,N',N',N",N"-Hexamethyl1-methylenephosphoranetriamine
Tris(dimethylamino)methylenephosphorane
Tris(dimethylamino)methylene-λ5-phosphane
Å a)
1.620(5)
1.684(3)
1.718(6)
1.457(3)
1.461(6)
1.115(1)
θa
N(1,2)–P–N(3)
N(1)–P–N(2)
C=P–N(1,2)
C=P–N(3)
P–N–C(11,21)
P–N–C(12,22)
P–N(3)–C
C–N(1,2)–C
C–N(3)–C
N–C–H b)
P=C–H
H–C–H
Σα(N(1),N(2)) d)
Σα(N(3)) d)
τ 1 e)
τ2 f )
deg a)
97.0(5)
115.2(13)
110.0(5)
127.1(8)
121.9(7)
122.6(7)
111.4(5)
115.0(5)
110.1(10)
111.1(3)
118.1 c)
117.6 c)
359.5(11)
332.9(13)
±1.5(18)
±178.4(21)
Cs assumed
CH2
H 3C
N
H 3C
H3 C
P
N
CH3
N
CH3
CH3
Local C2 symmetry of the N(CH3)2 groups and local C3v symmetry of the NCH3 groups were
assumed. The ED analysis was carried out by applying flexible restraints based on the results
of MP2/6-31G* calculations. The following results were obtained for the methyl conformation:
in the position that NMe2 has C2v symmetry, one C–H bond is staggered with respect to the
further N–C bond of the NMe2 group. The two CH3 groups are twisted about their respective
N–C bonds by 20.3(24)°.
The nozzle was at 140 °C.
a
) Estimated standard errors.
) Mean value.
c
) Assumed at the value from MP2/6-31G*
calculations.
d
) Sum of the angles at the N atoms.
e
) C=P–N–C(11,21) torsional angles from
the syn position.
f
) C=P–N–C(12,22) torsional angles from
the syn position.
b
Mitzel, N.W., Smart, B.A., Dreihäupl, K.-H., Rankin, D.W.H., Schmidbaur, H.: J. Am. Chem.
Soc. 118 (1996) 12673.
Landolt-Börnstein
New Series II/28D